Devices are known which turn flat articles such as letter envelopes, within a plane. Such devices have been used in inserting machines when envelopes are discharged from an insert station at which the envelope is stuffed with enclosures and the envelopes must be turned and reoriented before being conveyed for further processing by a downstream device such as a franking machine. Generally, such turner devices have the disadvantage of having to be an integral part of the inserting machine. Examples of devices which turn flat articles in inserting machines are shown in U.S. Pat. No. 4,726,461 issued Feb. 23, 1988 to J. Pokrinchak and U.S. Pat. No. 4,928,807 issued May 29, 1990 to D. Auerbach, both of which patents are assigned to the assignee of the present invention.
It is known to change the direction of travel for flat articles without changing the orientation of the articles, i.e., without rotating or turning the articles, referred to herein as a "right angle transfer". One example of a right angle transfer is a device that provides a one stage right angle change in direction in which the articles must be stopped in one direction before being conveyed in the right angled direction. Such a device is described in U.S. Pat. No. 4,909,374 issued Mar. 20, 1990 to M. Skrypalle and assigned to the assignee of the present invention.
Other right angle transfers are known to include two or more stages one of which includes deflection rollers that change the direction of travel by forty-five degrees (45.degree.) or less at each stage. An example of such an apparatus in a sorting machine is disclosed in U.S. Pat. No. 4,527,792 issued Jul. 9, 1985 to G. Burkhardt. The Burkhardt apparatus has several limitations which prevent it from being usable in an inserting machine. The apparatus is limited to changing direction of travel from a path parallel to a long edge of the mailpiece to a path of travel parallel to the short edge thereof. Furthermore, for all sized mailpieces, the Burkhardt apparatus requires a side-justified line of travel along the first direction of travel so that the deflection rollers can engage the article at the right moment to achieve an accurate change in direction. Typically, in an inserting machine the center line of travel of the mailpiece is fixed with the side guides being adjustable for handling various sized mailpieces.
Several versions of right angle transfers are known for use in inserting machines. In U.S. Pat. No. 5,180,154, issued on Jan. 19, 1993 to S. Malick and assigned to the assignee of the present invention, right angle transfer apparatus for conveying flat articles in an inserting machine is disclosed. The apparatus includes a deck having an input end for receiving an article from a first direction and a plurality of angled roller pairs for conveying the article over the deck in the second direction. The angled roller pairs engage a leading edge of the article only after the article has been released by a conveying means in the first direction. A registration wall, which extends at a right angle to the first direction, is positioned downstream from the angled roller pairs adjacent an output end of the deck. The leading edge of the article is driven against the registration wall as the article is released by the angled roller pairs. A third direction conveying means takes control of the article as soon as the article is against said registration wall.
Variations of the Malick '154 right angle transfer apparatus are also known. U.S. Pat. No. 5,180,159, issued on Jan. 19, 1993 to S. Malick and assigned to the assignee of the present invention, provides an adjustable right angle transfer apparatus for conveying flat articles in one of two directions. This apparatus is similar to the Malick '154 apparatus but the angled roller pairs for conveying in a second direction are mounted on a circular deck that can be rotated to position the rollers for conveying forty-five degrees to the left or to the right. U.S. Pat. No. 5,188,355, issued on Feb. 23, 1993 to K. Lowell et al. and assigned to the assignee of the present invention, provides a right angle transfer apparatus for sheets of paper. This apparatus is also similar to Malick '154 except for changes found to be necessary in moving individual sheets through the right angle transfer at high speed. For example, the registration wall was eliminated and spring guides were added to prevent the sheets from lifting off the deck.
The foregoing apparatus are configured for handling documents of a particular size, such as envelopes or sheets of paper. Although the foregoing apparatus work well for handling single size documents, they lack adjustment capability needed for handling multiple size documents. Typically, the foregoing apparatus requires the addition or removal of rollers angled at 45.degree. when the apparatus is used to handle larger or smaller documents respectively. Furthermore, the foregoing apparatus do not include a path for straight through processing in the third direction.